Easy opening container having shoulders to safeguard all severed edges

ABSTRACT

The sheet material of the container wall is offset to form a channel that conforms to the periphery of the tear portion of the wall. The channel has longitudinal side walls connected by a transverse web and a score groove defining the tear portion is formed in the web centrally thereof. The two longitudinal walls of the channel are in the form of two rounded shoulders to safeguard respectively the sharp edge of the severed tear portion of the container and the corresponding sharp severed edge of the remaining fixed portion of the container wall.

United States Patent Brown et al.

[ 11, 3,825,149 July 23, 1974 EASY OPENING CONTAINER HAVING SHOULDERS TOSAFEGUARD ALL SEVERED EDGES [75] Inventors: Omar L. Brown; James R.Schubert,

both of Dayton, Ohio [73] Assignee: Erma] C. Fraze, Dayton, Ohio [22]Filed: Dec. 6, 1972 [21] Appl. No.: 312,700

[52] 111.8. Cl. 220/54, 220/906 [51] Int. Cl .1 865d 17/20 [58] Field ofSearch 220/54, 90.6

[56] References Cited UNITED STATES PATENTS 12/1971 Elser 220/543,757,989 9/1973 Brown 220/54 Primary Examiner-George T. Hall Attorney,Agent, or Firm-Smyth, Roston & Pavitt [5 7 ABSTRACT The sheet materialof the container wall is offset to form a channel that conforms to theperiphery of the tear portion of the wall. The channel has longitudinalside walls connected by a transverse web and a score groove defining thetear portion is formed in the web centrally thereof. The twolongitudinal walls of the channel are in the form of two roundedshoulders to safeguard respectively the sharp edge of the severed tearportion of the container and the corresponding sharp severed edge of theremaining fixed portion of the container wall.

18 Claims, 6 Drawing Figures III , 'JIIIIIII w PATENTEB JUL 2 3 I9743.825 149 SHEEI 1 BF 2 PATENTED JUL 2 3 i974 SHEET 2 0F 2 walls, thetwo. side walls being suitably rounded BACKGROUND OF THE INVENTION Inthe construction of a prevalent type of easy opening container made ofsheet material, a tear portion of an end wall of the container isdefined by a scored groove and a pull tab attached to the tear portionis manually operable to cause severance of the sheet material along theline of scoring. The severance of the sheet material produces ahazardous sharp edge along the periphery of the displaced tear portionand a corresponding hazardous sharp edge is produced along the innerperiphery of the remaining adjacent fixed portion of the end wall. Thesesharp edges are extensive and, therefore, especially hazardous when thetear portion is nearly aslarge in area as the end wall of the containerand is completely severed from the end wall as in a socalled full panelpullout. i

A large number-of easy opening containers with full panel pullout endsis used for soft sweet fruit products, such as puddings which tend tocling to the inner surface of the pullout panel and tend to cling to theinner surface of the remaining fixed portion of the end wall of thecontainer. Commonly, a consumer is tempted to recover the adheringmaterial by licking the inner surface with his tongue, or by running afinger over the inner surfaces and too often such acts result in injuryto the consumer.

SUMMARY OF THE INVENTION I The primary object of the invention is tominimize the hazard represented not only by the sharp edge of thesevered tear portion of a container wall, but also by the correspondingsharp edge of the remaining fixed portion of the container wall.

In all embodiments of the invention disclosed herein, the attainment ofthis basic object involves offsetting the container wall in a patternthat conforms to the periphery of the tear portion of the wall.Preferably the offset is in the form of a channel that has opposite sidewalls interconnected by a transverse web and the tear portion of thecontainer is defined by a lineof scoring extending longitudinally of thechannel and located substantially centrally of the transverse web. Thelongitudinal side walls of the channel form two confronting bluntshoulders coextensive with a score line on opposite sides of the scoreline, which shoulders are of rounded cross section and are so positionedrelative to the scoring as to provide effective safeguards for the twosharp edges that are created by severance of the tear portion. Thus, oneextensive blunt shoulder safeguards the full length of the sharp edge ofthe severed tear portion of the container wall and a similar bluntshoulder is left with the remaining fixed portion of the container wallto safeguard the full length of the corresponding fixed sharp edge ofthe sheet material.

In a simplified practice of the invention, the channel walls are flaredoutward with the minimum width dimension of the channel at the bottom ofthe channel; i.e., at the scored web that interconnects the two side incross-sectional configuration.

In other practices of the invention, double folds are formed in each ofthe opposite side walls to result in rounded overhanging confrontingside walls that are reentrant to result in a channel configurationwherein the maximum width of the channel is at the scoredinterconnecting web and the minimum width of the channel is at thegap'between the two confronting rounded side walls. Thus, each side wallof the channel forms a rounded longitudinal shoulder that is relativelythick because the shoulder is made of two thicknesses of the sheetmaterial and the thick rounded shoulders are especially effective assafeguards since they overhang the scored web.

In one embodiment of the invention. wherein the channel is formed withdouble layer rounded shoulders, the channel opens inwardly to the innerface of the container wall. In an alternate embodiment of the invention,the channel with the confronting double thickness shoulders is openoutwardly to the outer face of the container wall. Each of thesealternate embodiments has its own particular advantages.

If the channel with the double layer rounded shoulders faces inwardly ofthe container, the scored web is elevated above the plane of the,container wall and is therefore fully accessible to the leading edge ofthe manually operable tab that severs the sheet material at the scoreline. Since the severing leading edge of the tab does not reach thescore line through the gap of the confronting double layer shoulders,the confronting shoulders may be very close together and may actuallytouch each other so that the two shoulders overhang the channel: web tomaximum extent and thus effectively overhang the two sharp severed edgeswhen the tear portion of the container wall is displaced.

An advantage of the inwardly facing channel with double layer roundedshoulders is that the medial plane of the thinned material at the bottomof the score groove is spaced outward from the inner surface of thecontainer wall by more than twice the thickness of the sheet material.Thus the sharp severed edges are correspondingly remote from the innersurfaces that tempt the user.

7 On the other hand, if the channel with the double layer shoulders isopen to the exterior of the container, the medial plane of the coinedsheet material at the bottom of the score groove in the interconnectingweb of the channel is offset inwardly from the outer face of thecontainer wall by more than two thicknesses of the sheet material. Thereis an advantage in this substantial inward spacing of the medial planeof the sharp edge of the severed full pull out panel fromthe outer faceof the panel to which the manually operable pull tab is attached andthere is also an advantage in the fact that the medial plane of thesharp severed edge of the fixed portion of the container wall is alsooffset inwardly from the outer face of the container wall by more thantwothicknesses of the sheet material. The confronting .reentrantshouldersof the outwardly facing channel must be spaced apartsufficiently to admit the severing leading edge of the pull tab, but theclearance may be relatively close. There is also an advantage in theoutwardly open channel configuration in that the leading edge of the tabtends to bow the channel web inwardly when it is initially swung inwardto sever the metal along the score groove. The initial bowing of the webincreases the transverse tension stress across the web and, accordingly,facilitates initial severance of the sheet materialat the score line.

A further feature of the invention is in the discovery of the reasonthat in many instances, the leading severing edge of the pull tab failsto make optimum pressure contact with the sheet material in the regionof the score groove. It has been found that with the leading end of theactuated pull tab swinging towards the scored metal in a somewhatarcuate path, the leading end is displaced horizontally from its initialposition relative to the score groove. Thus, the angular leading edge ofthe pull tab may appear to be initially positioned for positiveengagement with the score groove but actually the horizontal shift ofthe angular edge inherent in its arcuatemovement may cause failure ofthe angular edge to make optimum pressure contact with the scored metal.Based on this discovery the leading edge of the pull tab in thepreferred practices of the invention is slightly offset from the scoregroove in the direction to compensate for the slight horizontal shift ofthe leading edge.

The varous features and advantages of the invention may be understoodfrom the following detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of the fullpanel pull out end of a container embodying one practice of theinvention;

FIG. 2 is a greatly enlarged fragmentary cross section along the line 22 of FIG. 1 showing how an offset channel in the container wall formingconfronting blunt double layer shoulders may be open to the interior ofthe container with the scored web of the channel elevated above theplane of the container wall for ready access by the overhanging leadingend of the pull tab that is attached to the pull out panel;

FIG. 2a is a fragmentary sectionalview similar to FIG. 2 showing how thetwo confronting blunt double layer shoulders may be in mutual abutment;

FIG. 3 is a similar fragmentary sectional view showing how the offsetchannel with confronting blunt double thickness shoulders may be open tothe exterior of the container with the leading end of the pull tabextending through the gap between the two confronting shoulders of thechannel;

FIG. 4 is a plan view similar to FIG. 1 wherein the channel that isformed in the end wall of the container faces outwardly of the containerand the confronting blunt shoulders of the channel are of single layerthickness; and

FIG. 5 is an enlarged fragmentary section taken along the line 5 5 ofFIG. 4.

DESCRIPTION OF THE SELECTED EMBODIMENTS .OF THE INVENTION FIGS. 1 and 2indicate the construction of an easy opening container that embodies onepractice of the invention. The container has the usual cylindrical wallwhich is closed at its upper end by a transverse end wall 12 of ductilesheet material such as aluminum or aluminum alloy. The end wall 12 isattached to the cylindrical wall 10 in the usual manner by an upstandingseam 14 that is formed by interlocking flanges of the sheet material ina well known manner.

The transverse end wall 12 of the container has a line of weakness inthe form of a scored groove 15 which divides the end wall of thecontainer into two portions, namely, a tear portion in the form of afull pull out panel 16 and a surrounding narrow fixed portion 18 thatremains behind when the panel is completely severed from the can end.

In a well known manner a pull tab, generally designated 20, is attachedto the panel 16 by suitable means such as a hollow rivet 22, the pulltab being of well known type which functions as a lever, the tab havinga relatively short leading end portion 24 and a relatively long handleportion 25. The pull tab is formed with an ear 26 which is engaged bythe hollow rivet 22 and is connected to the leading end portion of thetab by a tongue 28. The tongue 28 is flexible to hingcdly connect thetab to the container wall and to serve as a fulcrum when the handleportion 25 of the tab is lifted to swing the leading end portion 24 ofthe tab downward for severance of the scored sheet material.

As may be seen in FIG. 4, the tab 20 is of generally ring-shapedconfiguration in plan and in a well known manner the sheet material ofthe tab is curled for stiffness along the inner and outer circumferencesof the ring-shaped configuration. By virtue of the curling of the metal,the tab 20 is hollow from below as may be seen in FIG. 2 and the leadingend portion of the tab has a leading end or piercing nose 30 which makespressure contact with the scored sheet material to initiate theseverance of the panel 16. The outer circumferential reinforcing curl ofthe tab has curled extensions 32 on opposite sides of the piercing nose30 and these two extensions are turned into the hollow interior of theleading end portion 24 of the tab to serve as interior reinforcementsfor the leading end of the tab.

It is to be noted that the piercing nose 30 of the leading end portion24 of the tab has an outer angular edge 34 and when the handle portion25 of the tab is lifted to initiate severance of the scored sheetmaterial, this leading angular edge swings in an arc into positiveengagement with the scored groove 15 for highly effective initialseverance of the scored metal. In accord with the teaching of theinvention, the piercing nose 30 of the tab is initially offset slightlyradially outwardly relative to the scored groove 15 instead of beingpositioned substantially symmetrically of the scored groove. Thisoutward offset compensates for the inward horizontal shift. of thepiercing nose 30 to cause the angular edge 34 of the piercing nose toenter into positive engagement with the scored groove 15 in the desiredmanner for a highly effective severance action on the scored sheetmetal.

The scored groove 15 which defines the pull out panel 16 is in thetransverse web 35 of a channel that is formed in the end wall of thecontainer by suitable dies, the channel following the periphery of thepanel with the scored groove centrally of the width of the transverseweb of the channel. The channel opens onto the interior of thecontainer; i.e., onto the inner face of the end wall 12 of the containerand has two opposite longitudinal side walls which as may be seen inFIG. 2 are formed with double bends to result in two confronting bluntlongitudinal shoulders 38 which are of curved cross sectionconfiguration and are of a thickness provided by two layers of the sheetmaterial. By virtue of the double bends of the sheet material, thelongitudinal side walls of the channel are reentrant, the width of thetransverse web 35 inside the channel being substantially greater thanthe entrance to the channel; i.e., greater than the gap between the twoconfronting longitudinal shoulders 38. Also by virtue of the doublefolding of the sheet material the medial plane of the FIG. 2a to providemaximum safeguard for the sharp severed edges of the sheet material. Theforming of the channel by offsetting the sheet material lends stiffnessto the end wall of the container and the double fold of the metal thatis integral with the fixed portion 18 of the end wall of the containerprovides substantial resistance to inward despression of the end wall bythe piercing nose 30 of the pull tab and thus facilitates initialseverance of the scored sheet material by the pull tab. In the secondembodiment shown in FIG. 3, the channel that is formed in the end wallof the container is reversed; i.e., opens outwardly onto the outer faceof the end wall. The channel has two side walls interconnected by atransverse web 42 and the side walls are double folded to provide twoconfronting blunt longitudinal shoulders 44 with a gap between theconfronting shoulders sufficient for admittance of the piercing nose 30of the pull tab. Thus, the medial plane of the coined material at thebottom of the scored groove is offset inwardly from the outer face ofthe container wall by more than twice the thickness of the sheetmaterial and accordingly the piercing nose 30a of the tab 20a is maderelatively long to reach the transverse web of the channel. Here againthe piercing nose 30a is initially slightly offset radially outwardlyrelative to the score groove 15a to compensate for the radially inwardshift of the piercing nose when the handle of the tab is elevated toinitiate severance of the sheet material.

One advantage of the structure shown in FIG. 3, is

that the medial plane of the sharp edge of the pull out panel that isproduced by severance of the scored sheet material is offset inwardlyfrom the outer face of the panel by more than twice the thickness of thesheet material. In like manner,the medial plane of the sharp severededge of the fixed portion 18a of the container end wall is offsetinwardly from the medial plane of the end wall by more than twice thethickness of the sheet ma- *terial. The inward offsetting of the twosharp severed edges increases the safeguard effectiveness of the tworounded shoulders 38a.

The third embodiment of the invention shown in FIGS. 4 and 5 is asimplified version in that the double folding of the side walls of thechannel is omitted. As shown in FIG. 5, the sheet material of thecontainer end wall is offset in a simple manner to form a channel havingtwo longitudinal side walls interconnected by a transverse web 46. Thechannel faces outwardly; i.e., opens onto the outer face of the end wallof the container so that the transverse web 416 of the channel is offsetinwardly from the medial plane of the end wall. The piercing nose 30b ofthe pull tab 20b extends through the medial plane of the end wall intothe channel and isslightly offset radially outwardly relative to thescored groove 48 in the transverse web. The medial plane of the sharpedge of the severed portion of the can end is offset inwardly from theouter face of the severed portion by at least 1% times the thickness ofi disclosure within the spirit and scope of the appended claims.

We claim: 1. In an easy opening container, the combination of:

a container wall of sheet material;

a line of weakness in the container wall defining a tear portion of thecontainer wall inwardly of the line of weakness that is at leastpartially removable from the remaining fixed portion of the containerwall that lies outwardly of the line of weakness;

means attached to said tear portion to sever the sheet materialgenerally along said line of weakness to at least partially sever thetear portion from the remaining fixed portion of the container wall,

the container wall being formed with offsets spaced from the twoopposite sides respectively of the line of weakness with the two offsetsforming two blunt shoulders in the container wall to safeguard the twosharp edges that are produced by severance ofthe sheet material alongthe line of weakness.

2. A combination as set forth in claim 1 in which said line of weaknessis a scored groove in the outer surface of the container wall;

and in which said severing means is a tab attached to the outer face ofthe tear portion in a hinged manner to permit one end of the tab toserve as a handle to swing the other end of the tab in a short arctowards the scored groove for severance of the sheet material,

said other end of the tab being formed with a leading edge to move alongsaid arc,

said leading edge being initially slightly offset relative to the scoredgroove outward towards said remaining fixed portion of the containerwall,

so that the arcuate movement of said leading edge causes the leadingedge to shift towards the scored groove to stress the sheet material atthe scored groove.

3. A combination as set forth in claim 2 in which the initial outwardoffset of the leading edge of the tab relative to the scored groove isof such magnitude as to cause the leading edge to enter the scoredgroove into positive engagement therewith to facilitate the severance ofthe sheet material at the scored groove.

4. A combination as set forth in claim 1 in which said transverse web isthinner than the rest of the sheet material of the container wall.

scored groove is positioned substantially midway be-' tween the twoblunt shoulders.

7. A combination as set forth in claim 5 in which said channel is opento the outer face of the container wall and said severing meansinitially extends between said confronting longitudinal shoulders in aposition intersecting the medial plane of the container wall.

8. A combination as set forth in claim in which the channel opens ontothe inner face of the end wall of the container so that the bluntsafeguard shoulder of the tear portion lies axially inwardly of thesharp edge of the severed tear section and the blunt safeguard shoulderof said remaining fixed portion of the container wall lies axiallyoutward of the sharp edge of the fixed portion that is produced byseverance of the sheet material along the line of weakness so that thetwo blunt shoulders reduce the hazard to the user of wiping contents ofthe container from the inner faces of said two portions of the containerwall.

9. A combination as set forth in claim 5 in which said channel opensonto the outer face of the end wall of the container so that the sharpedge of the tear portion produced by severance of the sheet materialalong the scored groove lies inwardly of the medial plane of the tearsection and the sharp edge of said remaining portion of the containerwall that is produced by the severance of the sheet material liesinwardly of the medial plane of said remaining portion of the containerwall.

10. A combination as set forth in claim 9 in which the two channel wallsflare outwardly with the minimum width of the channel at said transverseweb.

11. A combination as set forth in claim 5 in which the sheet materialthat forms each of the two side walls of the channel is formed with twobends with the sheet material bent back towards itself twice, one ofsaid two bends forming a blunt safeguard shoulder on the periphery ofthe tear portion of the container wall, the other of said two bendsforming a blunt safeguard shoulder on the inner margin of said remainingfixed outer portion of the container wall.

12. A combination as set forth in claim 11 in which said channel openstowards the outer face of the container wall, so that initial inwardpressure of said depressing means against the transverse web of thechannel tends to bow the web to place the web under transverse tensionto facilitate initial severance of the sheet material along the line ofweakness.

13. A combination as set forth in claim ll in which the two oppositeside walls of the channel are reentrant with a maximum width of thechannel at said transverse web.

14. A combination as set forth in claim 13 in which said channel is opento the inner face of the container wall.

15. A combination as set forth in claim 13 in which the channel is opento the outer face of the container wall.

16. A combination as set forth in claim 11 in which the line of weaknessis formed by a scored groove in said web so that by virtue of saiddouble bends the medial plane of the material at the bottom of thescored groove is spaced by more than twice the thickness of the sheetmaterial both from a face of said tear portion of the container wall andfrom a face of said remaining fixed portion of the container wall.

17. A combination as set forth in claim 16 in which said face of the twoportions of the container wall are the inner faces thereof.

18. A combination as set forth in claim 16 in which said faces of thetwo portions of the container wall are the outer faces thereof.

1. In an easy opening container, the combination of: a container wall ofsheet material; a line of weakness in the container wall defining a tearportion of the container wall inwardly of the line of weakness that isat least partially removable from the remaining fixed portion of thecontainer wall that lies outwardly of the line of weakness; meansattached to said tear portion to sever the sheet material generallyalong said line of weakness to at least partially sever the tear portionfrom the remaining fixed portion of the container wall, the containerwall being formed with offsets spaced from the two opposite sidesrespectively of the line of weakness with the two offsets forming twoblunt shoulders in the container wall to safeguard the two sharp edgesthat are produced by severance of the sheet material along the line ofweakness.
 2. A combination as set forth in claim 1 in which said line ofweakness is a scored groove in the outer surface of the container wall;and in which said severing means is a tab attached to the outer face ofthe tear portion in a hinged manner to permit one end of the tab toserve as a handle to swing the other end of the tab in a short arctowards the scored groove for severance of the sheet material, saidother end of the tab being formEd with a leading edge to move along saidarc, said leading edge being initially slightly offset relative to thescored groove outward towards said remaining fixed portion of thecontainer wall, so that the arcuate movement of said leading edge causesthe leading edge to shift towards the scored groove to stress the sheetmaterial at the scored groove.
 3. A combination as set forth in claim 2in which the initial outward offset of the leading edge of the tabrelative to the scored groove is of such magnitude as to cause theleading edge to enter the scored groove into positive engagementtherewith to facilitate the severance of the sheet material at thescored groove.
 4. A combination as set forth in claim 1 in which saidtransverse web is thinner than the rest of the sheet material of thecontainer wall.
 5. A combination as set forth in claim 1 in which thetwo offsets form a channel having opposite side walls that form the twoblunt shoulders in confronting relationship with each other.
 6. Acombination as set forth in claim 5 in which the scored groove ispositioned substantially midway between the two blunt shoulders.
 7. Acombination as set forth in claim 5 in which said channel is open to theouter face of the container wall and said severing means initiallyextends between said confronting longitudinal shoulders in a positionintersecting the medial plane of the container wall.
 8. A combination asset forth in claim 5 in which the channel opens onto the inner face ofthe end wall of the container so that the blunt safeguard shoulder ofthe tear portion lies axially inwardly of the sharp edge of the severedtear section and the blunt safeguard shoulder of said remaining fixedportion of the container wall lies axially outward of the sharp edge ofthe fixed portion that is produced by severance of the sheet materialalong the line of weakness so that the two blunt shoulders reduce thehazard to the user of wiping contents of the container from the innerfaces of said two portions of the container wall.
 9. A combination asset forth in claim 5 in which said channel opens onto the outer face ofthe end wall of the container so that the sharp edge of the tear portionproduced by severance of the sheet material along the scored groove liesinwardly of the medial plane of the tear section and the sharp edge ofsaid remaining portion of the container wall that is produced by theseverance of the sheet material lies inwardly of the medial plane ofsaid remaining portion of the container wall.
 10. A combination as setforth in claim 9 in which the two channel walls flare outwardly with theminimum width of the channel at said transverse web.
 11. A combinationas set forth in claim 5 in which the sheet material that forms each ofthe two side walls of the channel is formed with two bends with thesheet material bent back towards itself twice, one of said two bendsforming a blunt safeguard shoulder on the periphery of the tear portionof the container wall, the other of said two bends forming a bluntsafeguard shoulder on the inner margin of said remaining fixed outerportion of the container wall.
 12. A combination as set forth in claim11 in which said channel opens towards the outer face of the containerwall, so that initial inward pressure of said depressing means againstthe transverse web of the channel tends to bow the web to place the webunder transverse tension to facilitate initial severance of the sheetmaterial along the line of weakness.
 13. A combination as set forth inclaim 11 in which the two opposite side walls of the channel arereentrant with a maximum width of the channel at said transverse web.14. A combination as set forth in claim 13 in which said channel is opento the inner face of the container wall.
 15. A combination as set forthin claim 13 in which the channel is open to the outer face of thecontainer wall.
 16. A combination as set forth in claim 11 in which theline of weakness is formeD by a scored groove in said web so that byvirtue of said double bends the medial plane of the material at thebottom of the scored groove is spaced by more than twice the thicknessof the sheet material both from a face of said tear portion of thecontainer wall and from a face of said remaining fixed portion of thecontainer wall.
 17. A combination as set forth in claim 16 in which saidface of the two portions of the container wall are the inner facesthereof.
 18. A combination as set forth in claim 16 in which said facesof the two portions of the container wall are the outer faces thereof.